Deployment mechanism with integral actuation device

ABSTRACT

An apparatus includes an integral, additively manufactured, actuation device having a rigid portion comprising a shaped structural member and a flexible portion comprising a helical torsion spring. In a spacecraft application, a spacecraft appendage may be coupled with a deployment mechanism, the deployment mechanism including at least one integral, additively manufactured, actuation device having a rigid portion comprising a shaped structural member and a flexible portion comprising a helical torsion spring.

PRIORITY DATA

This application is a continuation application of U.S. patentapplication Ser. No. 16/817,286, entitled “Deployment Mechanism WithIntegral Actuation Device,” filed Mar. 12, 2020, which claims thebenefit of Provisional Application No. 62/817,440 filed on Mar. 12,2019, both of which are incorporated by reference herein in theirentirety.

TECHNICAL FIELD

This invention relates generally to a deployment mechanism, and moreparticularly to a deployment mechanism that includes an integral,additively manufactured, actuation device having a shaped structuralmember and a torsion spring.

BACKGROUND OF THE INVENTION

The assignee of the present invention manufactures and deploysspacecraft for, inter alia, communications and broadcast services. Suchspacecraft generally include a number of appendages such as solar arraypanels and antenna reflectors that are reconfigured from a launchconfiguration to an on orbit configuration using deployment mechanisms.Known deployment mechanisms, whether passive or motor driven, ofteninclude a number of springs, tensioning wires, hinges, dampers, as wellas underlying structural components. As a result, such deploymentmechanisms present a significant cost and reliability burden to thespacecraft design.

Accordingly, there is a need for improved deployment mechanisms fordeploying or otherwise reconfiguring the spacecraft appendages.

SUMMARY

According to some implementations, an apparatus, includes an integral,additively manufactured, actuation device having a rigid portioncomprising a shaped structural member and a flexible portion comprisinga helical torsion spring.

In some examples, a proximal end of the torsion spring may extend from awall of the rigid portion and a distal portion of the torsion spring maybe flexibly disposed with respect to the rigid portion. In someexamples, the distal portion may include a coupling feature. In someexamples, the coupling feature may include a threaded or press fitinterface configured to mate with a spacecraft appendage.

In some examples, the actuation device may be configured as a couplingnode having a plurality of legs, the shaped structural member being oneof the plurality of legs.

In some examples, the shaped structural member may be a thin-walledtube. In some examples, the thin-walled tube has a circularcross-section.

In some examples, the actuation device may be formed from a polymeric ormetallic material.

In some examples, each of a proximal end of the torsion spring and adistal end of the torsion spring may extend from a wall of the rigidportion and a central portion of the torsion spring is flexibly disposedwith respect to the rigid portion. In some examples, the central portionmay include a coupling feature. In some examples, the coupling featuremay include a threaded or press fit interface for mating to a spacecraftappendage.

According to some implementations, a spacecraft, includes a spacecraftappendage and a deployment mechanism connected to the spacecraftappendage, the deployment mechanism including at least one integral,additively manufactured, actuation device having a rigid portioncomprising a shaped structural member and a flexible portion comprisinga helical torsion spring.

In some examples, a proximal end of the torsion spring may extend from awall of the rigid portion and a distal portion of the torsion spring maybe flexibly disposed with respect to the rigid portion. In someexamples, the distal portion may include a coupling feature and thedeployment mechanism may be connected to the spacecraft appendage by wayof the coupling feature. In some examples, the coupling feature mayinclude a threaded or press fit interface for mating to the spacecraftappendage.

In some examples, the actuation device may be configured as a couplingnode having a plurality of legs, the shaped structural member being oneof the plurality of legs.

In some examples, the shaped structural member may be a thin-walled tubehaving a circular cross-section.

In some examples, the actuation device may be formed from a polymeric ormetallic material.

In some examples, each of a proximal end of the torsion spring and adistal end of the torsion spring may extend from a wall of the rigidportion and a central portion of the torsion spring may be flexiblydisposed with respect to the rigid portion. In some examples, thecentral portion includes a coupling feature. In some examples, thecoupling feature includes a threaded or press fit interface for matingto the spacecraft appendage.

BRIEF DESCRIPTION OF THE DRAWINGS

Features of the invention are more fully disclosed in the followingdetailed description of the preferred embodiments, reference being hadto the accompanying drawings, in which:

FIG. 1 illustrates an example of an actuation device in accordance withan implementation.

FIG. 2 illustrates two views of an actuation device according to afurther implementation.

FIG. 3 illustrates a deployment mechanism, according to animplementation.

FIG. 4 illustrates an example of a coupling feature of a torsion springengaging with coupling inserts of a spacecraft appendage.

FIG. 5 illustrates a view of an actuation device according to a furtherimplementation.

Throughout the drawings, the same reference numerals and characters,unless otherwise stated, are used to denote like features, elements,components, or portions of the illustrated embodiments. Moreover, whilethe subject invention will now be described in detail with reference tothe drawings, the description is done in connection with theillustrative embodiments. It is intended that changes and modificationscan be made to the described embodiments without departing from the truescope and spirit of the subject invention as defined by the appendedclaims.

DETAILED DESCRIPTION

Specific exemplary embodiments of the invention will now be describedwith reference to the accompanying drawings. This invention may,however, be embodied in many different forms, and should not beconstrued as limited to the embodiments set forth herein. Rather, theseembodiments are provided so that this disclosure will be thorough andcomplete, and will fully convey the scope of the invention to thoseskilled in the art.

It will be understood that when a feature is referred to as being“connected” or “coupled” to another feature, it can be directlyconnected or coupled to the other feature, or intervening features maybe present. Furthermore, “connected” or “coupled” as used herein mayinclude wirelessly connected or coupled. It will be understood thatalthough the terms “first” and “second” are used herein to describevarious features, these features should not be limited by these terms.These terms are used only to distinguish one feature from anotherfeature. Thus, for example, a first user terminal could be termed asecond user terminal, and similarly, a second user terminal may betermed a first user terminal without departing from the teachings of thepresent invention. As used herein, the term “and/or” includes any andall combinations of one or more of the associated listed items. Thesymbol “/” is also used as a shorthand notation for “and/or”.

The terms “spacecraft”, “satellite” and “vehicle” may be usedinterchangeably herein, and generally refer to any orbiting satellite orspacecraft system.

The present disclosure relates to an integral actuation device for adeployment mechanism. Advantageously, the device may be an additivelymanufactured component having a rigid portion and a flexible portion.The rigid portion may be configured as a structural member and theflexible portion may be configured as a torsion spring. At least a firstend of the torsion spring extends from a wall of the rigid portion. Insome implementations, a proximal end of the torsion spring extends froma wall of the rigid portion and a distal portion end of torsion springis flexibly disposed with respect to the rigid portion. In otherimplementations, both a proximal end and a distal second end of thetorsion spring extend from respective regions of the wall of the rigidportion while a central portion of the torsion spring disposed betweenthe proximal end and the distal end are flexibly disposed with respectto the rigid portion.

FIG. 1 illustrates an example of an actuation device in accordance withan implementation. The actuation device 100 is, advantageously, anintegral, additively manufactured component. The actuation device 100may be formed from a polymeric or metallic material, for example. In theillustrated example, the actuation device 100 includes a shapedstructural member 101. In some implementations, the structural member101 may be a thin-walled tube. In the illustrated example, thethin-walled tube has a circular cross-section, but an oval, ellipticalor polygonal cross-section may be contemplated by the presentdisclosure. The actuation device 100 also includes a flexible portion102 that may be configured to operate as a helical torsion spring. Aproximal end 103 of the flexible portion 102 extends from the rigidmember 101. A distal end 104 of the flexible portion 102 is movable withrespect to the rigid member 101. More particularly, application of aforce to the distal end 104 may compress or expand (“load”) the torsionspring with respect to a rest position.

In the illustrated implementation, the actuation device 100 alsoincludes a coupling feature 105 disposed proximate to the distal end 104of the flexible portion 102. Advantageously, the coupling feature 105may be an integral, additively manufactured feature of the actuationdevice 100. As described in further detail hereinbelow, the couplingfeature 105 may be configured to facilitate a threaded or press fitinterface with a coupling interface of a spacecraft appendage to bedeployed (not illustrated). In some implementations, for example, thecoupling feature 105 may be configured with a press fit characteristic,such that the coupling feature 105 may be compressed slightly in orderto reduce its outer diameter to pass through a corresponding hole in thecoupling interface of the spacecraft appendage.

FIG. 2 illustrates two views of an actuation device according to afurther implementation. The actuation device 200 may be regarded as athree-legged corner fitting, or coupling node, that includes a rigidportion that is configured to include three rigid members (legs),201(1), 201(2) and 201(3), extending outward from a common centralregion 206. In the illustrated example, the actuation device 200includes two flexible portions, 202(1) and 202(2), each flexible portionbeing associated with a respective structural member and configured tooperate as helical torsion spring (deployment coil). A proximal end203(1) of the flexible portion 202(1) extends from the rigid member201(1). Similarly, a proximal end 203(2) of the flexible portion 202(2)extends from the rigid member 201(2). As described above in connectionwith FIG. 1 , a distal end 204(i) of each flexible portion is movablewith respect to a respective rigid member 201(i). Moreover, theactuation device 200 also includes a coupling feature 205(i) disposedproximate to the distal end 204(i) of each flexible portion 202(i).Advantageously, the coupling features 205(i) may be integral, additivelymanufactured, features of the actuation device 200.

In the example of FIG. 2 , the actuation device is configured to havethree legs, of which each of two legs has an associated torsion spring.Actuation devices having two, four or more legs, of which one or morehave an associated torsion spring, are also contemplated by the presentdisclosure.

FIG. 3 illustrates a deployment mechanism, according to animplementation. In the illustrated implementation, a deploymentmechanism 300 includes two actuation devices, 320(1) and 320(2) and acoupling node 322. The deployment mechanism 300 may be configured as (oras part of) a closed truss structure form fabricated using one or morethe techniques disclosed in U.S. Pat. No. 10,227,145, assigned to theassignee of the present invention, the disclosure of which is herebyincorporated by reference in its entirety into the present application.In the illustrated example, actuation devices, 320(1) and 320(2) aremechanically coupled by way of a strut element 310 and include,respectively, associated torsional springs 302(1) and 302(2). Aspacecraft appendage 3000 may be coupled with the deployment mechanism300 by way of respective distal ends of the torsional springs 302(1) and302(2). An exploded view of such an arrangement is shown in Detail A. Asdescribed in more detail hereinbelow, the distal end of each of thetorsional springs 302(1) and 302(2) include a press fit assembly thatengages with a respective coupling insert 3004(1) and 3004(2) of thespacecraft appendage 3000. Detail B and Detail C illustrate,respectively, a stowed and a deployed configuration of the assembly ofthe spacecraft appendage 3000 with the deployment mechanism 300.

Advantageously, the actuation devices 320(1) and 320(2) may beconfigured to provide for controlled deployment of appendage 3000 to apredefined angle. In the stowed configuration (Detail B) the appendage3000 may be secured by a releasable hold-down device (not illustrated)in a position that causes a torsional pre-load of the torsional springs302(1) and 302(2). When the hold-down device is released, deployment ofthe panel may be passively driven by the springs 302(1) and 302(2)relieving the torsional pre-load.

FIG. 4 illustrates an example of a coupling feature of a torsion springengaging with coupling inserts of a spacecraft appendage 4000. Referringfirst to Detail D, in the illustrated example, the coupling feature 405may be configured as a press fit arrangement disposed at or near thedistal end of a torsion spring (not illustrated). The coupling feature405 may be configured to engage with walls of a mating couplinginterface 4004. Such an arrangement may allow quick assembly where, inthe illustrated example, the coupling feature 405 is configured as amale press fit arrangement that engages with the mating couplinginterface 4004, which is configured as a complementary female press fitinterface of the spacecraft appendage 4000. As may be observed in DetailE, a centerline relief provides space for a compressive deformation ofthe coupling feature 405 while a top lip portion is configured toprevent inadvertent retraction of the coupling feature 405 afterengagement with the coupling interface 4004.

Referring again to FIG. 2 , in some implementations, one or all of thelegs 201(1), 201(2) and 201(3) may have different lengths. As a result,an actuation device 200 may be asymmetrical and facilitate assembly intoa closed form truss structure as described in U.S. Pat. No. 10,227,145.Advantageously, two actuation devices 200 may be mutually complementary.As a result, in configurations where, as in the illustrated example,201(1), 201(2) and 201(3) are mutually orthogonal, a four-cornerrectangular deployment mechanism may be contemplated where each of thefour corners is formed from an identical actuation device 200.Alternatively, more complex geometric shapes can be realized by alteringthe angle between the legs. For example, a “soccer ball” arrangementthat includes twelve pentagonal and twenty hexagonal faces can befabricated utilizing just two different designs.

It will be appreciated that dimensions of deployment device 200 may bescaled to accommodate various spacecraft requirements for loading,dynamic response, deployment angle, size, and shape.

FIG. 5 illustrates a view of an actuation device according to a furtherimplementation. Similarly to the actuation device 200 described above inconnection with FIG. 2 , the actuation device 500 may be regarded as athree-legged corner fitting, or coupling node, that includes a rigidportion that is configured to include three shaped structural members(legs), 501(1), 501(2) and 501(3), extending outward from a commoncentral region 506. In the illustrated example, the actuation device 500includes two flexible portions, 502(1) and 502(2), each flexible portionbeing associated with a respective member and configured to operate ashelical torsion spring (deployment coil). A proximal end 503(1) and adistal end 504(1) of the flexible portion 502(1) extends from the rigidmember 501(1). Similarly, a proximal end 503(2) and a distal portion504(2) of the flexible portion 502(2) extend from the rigid member501(2). The actuation device 500 includes a coupling feature 505(i) thatis disposed between the proximal end 503(i) and the distal end 504(i) ofeach flexible portion 502(i). Advantageously, the coupling features505(i) may be integral, additively manufactured, features of theactuation device 500.

In addition to providing torque for deployment of an appendage, it iscontemplated that the deployment device 200 may include one or moredamping features. For example, additional torsion springs (notillustrated) may be configured to provide passive damping for thedeployment mechanism. For example, one or more mirrored helicoil springsmay be configured for this purpose. Alternatively or in addition, aportion of one or more legs may be configured to include a passivedampening feature to help reduce overall dynamic loading to thespacecraft and subassemblies

Thus, a deployment mechanism that includes an integral, additivelymanufactured, actuation device having a shaped structural member and atorsion spring has been disclosed. It will thus be appreciated thatthose skilled in the art will be able to devise numerous systems andmethods which, although not explicitly shown or described herein, embodysaid principles of the invention and are thus within the spirit andscope of the invention as defined by the following claims.

What is claimed is:
 1. An actuation apparatus, comprising: a first tube;a first helical torsion spring connected at a first end to the firsttube, the first helical torsion spring wraps around the first tube, thefirst helical torsion spring and the first tube together are a firstintegral and additively manufactured structure; and a first couplingattached to the first helical torsion spring.
 2. The actuation apparatusof claim 1, wherein: the first tube, the first helical torsion springand the first coupling together are an integral and additivelymanufactured structure; and the first coupling is configured to attachto an appendage of a spacecraft.
 3. The actuation apparatus of claim 1,wherein: the first helical torsion spring includes the first end and asecond end, the first end the second end extend from a wall of the firsttube.
 4. The actuation apparatus of claim 1, wherein: the first tube ishollow.
 5. The actuation apparatus of claim 1, wherein: the first tubehas a circular cross-section.
 6. The actuation apparatus of claim 1,further comprising: a plurality of connected legs each of which areorthogonal to each other, the first tube comprises one of the legs. 7.The actuation apparatus of claim 1, wherein: the first helical torsionspring includes the first end and a second end, the first coupling isattached to the first helical torsion spring at the second end of thefirst helical torsion spring.
 8. The actuation apparatus of claim 1,wherein: the first tube and the first helical torsion spring are formedfrom a polymeric or metallic material.
 9. The actuation apparatus ofclaim 1, further comprising: a second tube connected to the first tube;a second helical torsion spring connected to the second tube, the secondhelical spring wraps around the second tube; and a second couplingattached to the second helical torsion spring.
 10. The actuationapparatus of claim 9, wherein: the first coupling and the secondcoupling are configured to attach to an appendage of a spacecraft. 11.The actuation apparatus of claim 9, wherein: the first tube isorthogonal to the second tube.
 12. The actuation apparatus of claim 1,wherein: the first coupling is configured to attach to an appendage of aspacecraft; and the first helical torsion spring is configured to deploythe appendage by relieving a torsional pre-load of the first helicaltorsion spring.
 13. A spacecraft deployment apparatus configured todeploy an appendage of a spacecraft, the apparatus comprising: a firstshaped structural member; and a first spring connected to the firstshaped structural member, the first spring wraps around the first shapedstructural member, the first spring and the first shaped structuralmember together are an integral and additively manufactured structure;and a coupling attached to the first spring and configured to attach tothe appendage of the spacecraft.
 14. The spacecraft deployment apparatusof claim 13, further comprising: a second shaped structural memberconnected to the first shaped structural member; a second springconnected to the second shaped structural member, the second springwraps around the second shaped structural member; and a second couplingattached to the second spring and configured to attach to the appendageof the spacecraft.
 15. The spacecraft deployment apparatus of claim 14,wherein: the first spring and the second spring are configured to deploythe appendage by relieving a torsional pre-load of the first helicaltorsion spring and the second helical torsion spring.
 16. A spacecraft,comprising: a spacecraft appendage; and a deployment mechanismcomprising: a first shaped structural member, a first spring connectedto the first shaped structural member, the first spring wraps around thefirst shaped structural member, the first spring and the first shapedstructural member together are an integral and additively manufacturedstructure, and a first coupling attached to the first spring and thespacecraft appendage.
 17. The spacecraft of claim 16, wherein: the firstshaped structural member, the first spring and the first couplingtogether are an integral and additively manufactured structure.
 18. Thespacecraft of claim 16, wherein: the first spring is configured todeploy the appendage by relieving a torsional pre-load of the firstspring.
 19. The spacecraft of claim 16, further comprising: a secondshaped structural member connected to the first shaped structuralmember; a second spring connected to the second shaped structuralmember, the second spring wraps around the second shaped structuralmember; and a second coupling attached to the second spring andconfigured to attach to the appendage of the spacecraft.
 20. Thespacecraft of claim 19, wherein: the first spring and the second springare configured to deploy the appendage by relieving a torsional pre-loadof the first helical torsion spring.